Username enumeration in BusyBox httpd system password authentication
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-203.
Summary
BusyBox httpd, when configured with system password authentication, may let a remote attacker tell existing usernames from non-existing ones in certain build configurations. The flaw is an observable discrepancy (CWE-203) in authentication failure behavior. An unauthenticated attacker needs a high-complexity setup, and the impact is limited to username enumeration. Default BusyBox builds with shadow password support are not affected.
Written with Claude Haiku 5.5 from the sources below · 2026-10-27
Description from the CNA
A flaw was found in BusyBox's httpd web server. When configured with system password authentication, a user existence oracle may exist in certain build configurations. An attacker could distinguish existing from non-existing usernames by observing authentication failure behavior. Impact is limited to username enumeration and requires non-default compile options or uncommon password file states; default BusyBox builds with shadow password support are not affected.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
The sources list no fixed version for Red Hat Hardened Images.
Written with Claude Haiku 5.5 from the sources below · 2026-10-27
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
Not affected: 1 product
- Red Hat Hardened Images
Timeline
- 2026-10-13 Threatist record created from CVE-2026-88834
- 2026-10-13 Alias added: GHSA-g83p-qwfp-8p23
- 2026-10-15 Affected versions changed · Red Hat
- 2026-10-15 CVSS score added · Red Hat
References
More Red Hat vulnerabilities
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Sources
- CVE-2026-88834 · CVE Program
- CVE-2026-88834 · NVD
- FIRST EPSS
- GHSA-g83p-qwfp-8p23 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-88834 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences